Belle Prater's Boy, by Ruth White, 1996

When Gypsy's aunt, Belle Prater, up and disappears from out of her bed, and Uncle Everett takes to drink, pretty soon her cousin Woodrow moves in next door with Granny and Grandpa Ball. Woodrow wears Coke-bottle glasses and bears the brunt of their Virginia mining town's curiosity over his mother's disappearance. Middle-grade realism; warm, thoughtful, unsentimentalized, unexpected. Strongly recommended.